Dear Deep, It appears that in your company, primary and secondary duties are not well-defined. Generally, managers/HODs are expected to spend 80% of their time on primary duties and 20% on secondary duties. Twenty percent roughly works out to one working day per week. You should issue a circular to this effect.
Secondly, the managers do not take pride in selecting GETs. This could be because they might not have an affiliation towards the organization. I have been told that when Google hires someone, they generally have a five-round selection process. Managers or other seniors nominate themselves for the interviews. Therefore, the selection may take place in the Asian continent, but the interviewer may be nominated from Europe or the US. Their voluntary nomination speaks volumes. Interviewers volunteer to nominate because Google places great importance on building the company's culture. They give more importance to whether the candidate is fit to be a Googler or not than anything else.
Recommendation for Sensitizing Senior Management
I recommend sensitizing your senior management personnel on the role of recruitment in building the organization's culture. You have asked for their motivation because they do not understand the gravity behind it. The selection of misfit candidates spells disaster for the company. Possibly, they may leave on their own or they may be asked to leave, but they leave their legacy behind, and this legacy pollutes the organization's culture.
One way to sensitize the managers on the seriousness of recruitment is to train them in "Interview Handling Skills." If you are interested in training them, feel free to contact me.
Thanks,
Dinesh Divekar